John b



JOHN n. MITCHELL, or EvANs'roN, ILLINOIS, AssIeNoa To WILLIAMH. MINEB,or

cHAzY, NEW Yoan.

INSULATION FOR REFRIGERATOBFCARS AND THE LIKE.

Specification of Letters Patent.

Patented Aug. 26, 1919.

Application led March 4, 1918. Serial No. 220,331.

To all whom t may concern:

Be it known that I, JOHN R. MITCHELL, a citizen of the United States,residing at Evanston, in the county of Cook and State of Illinois, haveinvented a certain new and useful Improvement in Insulation forRefrigerator-Cars and the like, of which the following is a full, clear,concise, and exact description, reference being had to the accompanyingdrawings, forming a part. of this s ecification.

This invention relates to improvements in insulation for refrigeratorcars and the like.

One object of the invention is to provide a comparatively inexpensiveand simple form of insulation for refrigerator packing, moreparticularly adapted for refrigerator cars and which may be applied withvery small effort.

Another and more specific object of the invention is to provide aninsulation of the type above indicated which may be substituted for themost common form of insulation now employed on refrigerator cars andwhich will prove more effective while at the same time being obtainableat less expense.

In the drawing forming a part of this specification, Figure 1 is ahorizontal,l sectional view of a portion of a side of a refrigeratorcar, the section extending through the side doors of the car and showingthe latter in closed position. Fig. 2 is an enlarged, sectional view,showing the edge portion of one of the refrigerator car members with myimprovements associated therewith, the position of the insulation beingthat occupied when the doors of the car are open and there is nopressure upon the insulation. Fig. 3 is a view corresponding to Fig.

2, but illustrating the condition of the parts.

when the doors are closed and the insulation is under compression. AndFig. 4 is an elevational view of the edge of one of the insulatedmembers with the outer fabric or padding removed to more clearlyillustrate the detailed construction of the spring backing strip.

In said drawing, 10 and 11 denote two pivoted side doors of arefrigerator car having beveled meeting edges in the usual manner, saiddoors being pivoted to the side wall 12 of the car in the usual manner.As is customary, insulation or packing is provided between tlie meetingedges of the door and car wall and the meeting edges of the doorsthemselves to thereby prevent tiansference of heat from one side of thecar wall to the other when the car is in transit.

Inasmuch as the insulation is the same in all places, it is necessary todescribe the insulation for one part only.

.Referring now t0 Figs. 2, 3 and 4, the sidewall 12 is shown as providedwith a vertically extending groove or recess 13 along its edge againstwhich the opposed edge of the door 10 bears when the latter is 1n closedposition. Said groove or recess 13, as shown, is of the form and sizenow commonly found in refrigerator cars heretofore employing theso-called .La Flare refrigerator door packing, the one most general inuse and my improved insulation is so designed that it may be substitutedfor the said La Flare insulation to thereby minimize expense to theusers. Secured to the wall of the car along each edge of the groove 13are sheet metal spring backing strips 14-14, each ofsaid strips 14 beingsecured along its edge at one side of the groove 13 by any suitablemeans, such as the series of nails 15, and preferably the edge of thecar curled, as indicated at 1 so as to facilitate the compressing actionwithout danger of tearing the fabric placed thereover.

As clearly Shown in Fig. 4, each strip 14 is formed in relatively shortsections 114-114, each of which is independently flexible. This may beconveniently done by slitting the strips 14 at intervals, as indicatedat 18-'18, although should it be desired, individual sections may beemployed. The object of providing the strip with independently flexiblesections is to insure a proper spring backing throughout the entirelength of the covering fabric and to obviateany variation which mightoccur from warping or deformation of the opposing edge of the door.Also, heretofore where a. single backing element has been emplo ed forthe fabric, if the backing strip itself as become warped, as in the caseof a wood insure a more uniform springbacking thanv heretofore andwithout increased expense.

The spring strip may be covered in any desired manner, as for instance,by felting 19 tacked or nailed to the edge of the car wall and over thefelting may be placed a facing of canvas 20.

As clearly appears from Fig. 3, when the insulation is under.compression, the fabrics are supported substantially throughout theentire Width of the groove or recess 13 with the exception of a slightspacing at the center. This spring support is insured throughout theentire length of the groove due to the sectional .formation of thespring strlps, except possibly in isolated points where the wood of adoor may be unduly warped or some unusual injury ha's occurred to theinslllation.

It is evident that the spring strips may be v manufactured with simplemachinery and at small expense and that the same can be applied withoutdiiiiculty inasmuch as nailing is all that is required.

1. In a packing for refrigerator car doors and the like, the combinationof a structural element formed with a recess extending along the line ofclosing, and a compressiblev recessed structural element, and sheetmetal' springs attached along opposite sides of said recess andextending to near the middle of the same along the lnner side of thecovering approximately in contact therewith from the edges of the recessto the free edges of the springs, and subdivided into a plurality ofindependently bendable sections.

2. In a packing for refrigerator car doors and the like, the combinationof a structural element formed with a recess extending along the line ofclosing, and a compressible packing extending along 'said recess andadapted to be engaged and compressed b 'an opposing structural element,one of sai structural elements being a door, said packing comprising aflexible covering arranged over said recess and attached to the saidrecessed structural element, land a sheet metal spring attached alongthe side of said recess, and extending over the same along the innerside of the covering approximately in contact therewith from the edge ofthe 'recess to the free edge of the spring, and

subdivided into a plurality of independently bendable sections.

In witness that' I claim the have hereunto subscribed my name this 14thday of Feb., 1918.

JOHN R. MITCHELL.

foregoing I

